Smooth scrolling of a structured document presented in a graphical user interface with bounded memory consumption

1. One or more computer-readable non-transitory storage media embodying software that is operable when executed to:

detect an event corresponding to scrolling a structured document comprising a plurality of elements that can be presented in a graphical user interface (GUI) of an application executed by one or more main processors of a device, the GUI being scrollable along at least one axis relative to a display of the device showing the GUI, wherein the structured document further comprises a plurality of regions; and

in response to detection of the event:

determine a plurality of particular regions of the structured document from the plurality of regions, the plurality of particular regions comprising:

a first region of the structured document currently displayed within the GUI;

a region immediately above the first region and not currently displayed within the GUI; and

a region immediately below the first region and not currently displayed within the GUI;

determine a first set of elements of the plurality of elements of the structured document and a second set of elements of the plurality of elements of the structured document, wherein:

placement of a first element of the plurality of elements of the structured document into the first set of elements of the plurality of elements of the structured document is based at least on a first distance of the first element to the GUI and whether the first element is a text element; and

placement of a second element of the plurality of elements of the structured document into the second set of elements of the plurality of elements of the structured document is based at least on:

a second distance of the second element to the GUI;

whether the second element is a media element; and

whether the second element is in the plurality of particular regions;

concurrently cause:

the one or more of the main processors to render the first set of elements of the plurality of elements of the structured document for presentation in the GUI, without rendering elements of the plurality of elements of the structured document not within the first set of elements of the plurality of elements of the structured document; and

one or more graphics processors of the device to render the second set of elements of the plurality of elements of the structured document for presentation within the GUI, without rendering elements of the plurality of elements not within the second set of elements of the structured document.

2. The one or more media of claim 1 , wherein the first set of elements comprises one or more frames comprising text content of the structured document.

3. The one or more media of claim 1 , wherein at least one of the plurality of regions encompasses the GUI.

4. The one or more media of claim 1 , wherein the first and second sets of elements of the structured document are determined based at least on one or more preferences of a user associated with the device.

5. The one or more media of claim 1 , wherein the event comprises scrolling through the structured document being stopped at least momentarily.

6. The one or more media of claim 1 , wherein the device is a smartphone.

7. The media of claim 1 , wherein the first and second sets of elements of the structured document are determined at least in part based on social factors of a user associated with the device.

8. The one or more media of claim 1 , wherein the first distance includes a first number of pixels and the second distance includes a second number of pixels.

9. A method comprising:

by one or more main processors of a device, detecting an event corresponding to scrolling a structured document comprising a plurality of elements that can be presented in a graphical user interface (GUI) of an application executed by one or more main processors of the device, the GUI being scrollable along at least one axis relative to a display of the device showing the GUI, wherein the structured document further comprises a plurality of regions; and

in response to detection of the event:

by the one or more of the main processors, determining a plurality of particular regions of the structured document from the plurality of regions, the plurality of particular regions comprising:

a first region of the structured document currently displayed within the GUI;

a region immediately above the first region and not currently displayed within the GUI; and

a region immediately below the first region and not currently displayed within the GUI;

by the one or more of the main processors, determining a first set of elements of the plurality of elements of the structured document and a second set of elements of the plurality of elements of the structured document, wherein:

placement of a first element of the plurality of elements of the structured document into the first set of elements of the plurality of elements of the structured document is based at least on a first distance of the first element to the GUI and whether the element is a text element; and

placement of a second element of the plurality of elements of the structured document into the second set of elements of the plurality of elements of the structured document is based at least on:

a second distance of the second element to the GUI;

whether the second element is a media element; and

whether the second element is in the plurality of particular regions; and

concurrently:

by the one or more of the main processors, rendering the first set of elements of the plurality of elements of the structured document for presentation in the GUI, without rendering elements of the plurality of elements of the structured document not within the first set of elements of the plurality of elements of the structured document; and

one or more graphics processors of the device rendering the second set of elements of the plurality of elements of the structured document for presentation in the GUI, without rendering elements of the plurality of elements not within the second set of elements of the structured document.

10. The method of claim 9 , wherein the first set of elements comprises one or more frames comprising text content of the structured document.

11. The method of claim 9 , wherein at least one of the plurality of regions encompasses the GUI.

12. The method of claim 9 , wherein the first and second sets of elements of the structured document are determined based at least on one or more preferences of a user associated with the device.

13. The method of claim 9 , wherein the event comprises scrolling through the structured document being stopped at least momentarily.

14. The method of claim 9 , wherein the device is a smartphone.

15. The method of claim 9 , wherein the first and second sets of elements of the structured document are determined at least in part based on social factors of a user associated with the device.

16. The method of claim 9 , wherein the first distance includes a first number of pixels and the second distance includes a second number of pixels.

17. An apparatus comprising:

one or more main processors;

one or more graphics processors;

one or more communication interfaces;

a display; and

a memory coupled at least to the one or more main processors and comprising instructions executable at least by the one or more main processors, the one or more main processors being operable when executing the instructions to:

detect an event corresponding to scrolling a structured document comprising a plurality of elements that can be presented in a graphical user interface (GUI) of an application executed by the one or more of the main processors, the GUI being scrollable along at least one axis relative to the display showing the GUI, wherein the structured document further comprises a plurality of regions; and

in response to detection of the event:

determine a plurality of particular regions of the structured document from the plurality of regions, the plurality of particular regions comprising:

a first region of the structured document currently displayed within the GUI;

a region immediately above the first region and not currently displayed within the GUI; and

a region immediately below the first region and not currently displayed within the GUI;

determine a first set of elements of the plurality of elements of the structured document and a second set of elements of the plurality of elements of the structured document, wherein:

placement of a first element of the plurality of elements of the structured document into the first set of elements of the plurality of elements of the structured document is based at least on whether the first element is a text element; and

placement of a second element of the plurality of elements of the structured document into the second set of elements of the plurality of elements of the structured document is based at least on:

 a second distance of the second element to the GUI;

 whether the second element is a media element; and

 whether the second element is in the plurality of particular regions;

concurrently cause:

the one or more of the main processors to render the first set of elements of the plurality of elements of the structured document for presentation in the GUI, without rendering elements of the plurality of elements of the structured document not within the first set of elements of the plurality of elements of the structured document; and

the one or more of the graphics processors to render the second set of elements of the plurality of elements of the structured document for presentation in the GUI, without rendering elements of the plurality of elements not within the second set of elements of the structured document.

18. The apparatus of claim 17 , wherein the first set of elements comprises one or more frames comprising text content of the structured document.

19. The apparatus of claim 17 , wherein at least one of the plurality of regions encompasses the GUI.

20. The apparatus of claim 17 , wherein the first distance includes a first number of pixels and the second distance includes a second number of pixels.